diff options
Diffstat (limited to 'pc-bios/optionrom')
| -rw-r--r-- | pc-bios/optionrom/linuxboot.S | 47 | ||||
| -rw-r--r-- | pc-bios/optionrom/optionrom.h | 21 |
2 files changed, 61 insertions, 7 deletions
diff --git a/pc-bios/optionrom/linuxboot.S b/pc-bios/optionrom/linuxboot.S index 748c831160..5bc0af08e0 100644 --- a/pc-bios/optionrom/linuxboot.S +++ b/pc-bios/optionrom/linuxboot.S @@ -76,14 +76,45 @@ boot_kernel: copy_kernel: + /* Compute initrd address */ + mov $0xe801, %ax + xor %cx, %cx + xor %dx, %dx + int $0x15 + + /* Output could be in AX/BX or CX/DX */ + or %cx, %cx + jnz 1f + or %dx, %dx + jnz 1f + mov %ax, %cx + mov %bx, %dx +1: + + or %dx, %dx + jnz 2f + addw $1024, %cx /* add 1 MB */ + movzwl %cx, %edi + shll $10, %edi /* convert to bytes */ + jmp 3f + +2: + addw $16777216 >> 16, %dx /* add 16 MB */ + movzwl %dx, %edi + shll $16, %edi /* convert to bytes */ + +3: + read_fw FW_CFG_INITRD_SIZE + subl %eax, %edi + andl $-4096, %edi /* EDI = start of initrd */ /* We need to load the kernel into memory we can't access in 16 bit mode, so let's get into 32 bit mode, write the kernel and jump back again. */ /* Reserve space on the stack for our GDT descriptor. */ - mov %esp, %ebp - sub $16, %esp + mov %esp, %ebp + sub $16, %esp /* Now create the GDT descriptor */ movw $((3 * 8) - 1), -16(%bp) @@ -108,10 +139,18 @@ copy_kernel: /* We're now running in 16-bit CS, but 32-bit ES! */ /* Load kernel and initrd */ + pushl %edi + read_fw_blob_addr32_edi(FW_CFG_INITRD) read_fw_blob_addr32(FW_CFG_KERNEL) - read_fw_blob_addr32(FW_CFG_INITRD) read_fw_blob_addr32(FW_CFG_CMDLINE) - read_fw_blob_addr32(FW_CFG_SETUP) + + read_fw FW_CFG_SETUP_ADDR + mov %eax, %edi + mov %eax, %ebx + read_fw_blob_addr32_edi(FW_CFG_SETUP) + + /* Update the header with the initrd address we chose above */ + popl %es:0x218(%ebx) /* And now jump into Linux! */ mov $0, %eax diff --git a/pc-bios/optionrom/optionrom.h b/pc-bios/optionrom/optionrom.h index ce436085d9..f1a9021ec1 100644 --- a/pc-bios/optionrom/optionrom.h +++ b/pc-bios/optionrom/optionrom.h @@ -51,8 +51,6 @@ .endm #define read_fw_blob_pre(var) \ - read_fw var ## _ADDR; \ - mov %eax, %edi; \ read_fw var ## _SIZE; \ mov %eax, %ecx; \ mov $var ## _DATA, %ax; \ @@ -68,6 +66,8 @@ * Clobbers: %eax, %edx, %es, %ecx, %edi */ #define read_fw_blob(var) \ + read_fw var ## _ADDR; \ + mov %eax, %edi; \ read_fw_blob_pre(var); \ /* old as(1) doesn't like this insn so emit the bytes instead: \ rep insb (%dx), %es:(%edi); \ @@ -80,7 +80,22 @@ * * Clobbers: %eax, %edx, %es, %ecx, %edi */ -#define read_fw_blob_addr32(var) \ +#define read_fw_blob_addr32(var) \ + read_fw var ## _ADDR; \ + mov %eax, %edi; \ + read_fw_blob_pre(var); \ + /* old as(1) doesn't like this insn so emit the bytes instead: \ + addr32 rep insb (%dx), %es:(%edi); \ + */ \ + .dc.b 0x67,0xf3,0x6c + +/* + * Read a blob from the fw_cfg device in forced addr32 mode, address is in %edi. + * Requires _SIZE and _DATA values for the parameter. + * + * Clobbers: %eax, %edx, %edi, %es, %ecx + */ +#define read_fw_blob_addr32_edi(var) \ read_fw_blob_pre(var); \ /* old as(1) doesn't like this insn so emit the bytes instead: \ addr32 rep insb (%dx), %es:(%edi); \ |